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Topic: Rear end noise (Read 2091 times) previous topic - next topic

Rear end noise

I have a lot of noise in the rear end of my car, sometimes it sounds like the differential other times it sounds like a bearing.  My question; do these cars 1986 Cougars have a lot of noise ya know it's an old car, will some of this noise quiet down after replacing the bearings or will I always have some road noise?

Rear end noise

Reply #1 –
Mine have been pretty quiet overall.

Dont rule out drum brakes as the source. If one of the springs go, it can make a ton of noise randomly, plus you will lose brakes.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Rear end noise

Reply #2 –
How many miles are on the car and does it make the noise all the time or when turning or in reverse only or when the brakes are applied or ???

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

noise in the rear

Reply #3 –
Quote from: Aerocoupe;459496
How many miles are on the car and does it make the noise all the time or when turning or in reverse only or when the brakes are applied or ???


91,000 miles on the car, makes noise after 30 miles per hour, all the time not much difference when turning, although the hum isn't as loud if you drive over 65 mph.  I am going to have the bearing replaced since that will service my differential too, then see what it sounds like, let me know your thoughts, please.

Rear end noise

Reply #4 –
Might be rear wheel bearings. Which means you might need rear axles. You can get "axle savers", which are bushings that go over the worn part of the axle, but their success as a repair is dubious
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Worn Axle

Reply #5 –
Quote from: Thunder Chicken;459504
Might be rear wheel bearings. Which means you might need rear axles. You can get "axle savers", which are bushings that go over the worn part of the axle, but their success as a repair is dubious


So why do you think I'd have a worn axle?  And how do you tell, by looking?

Rear end noise

Reply #6 –
Id be surprised if the axle is bad. Ive had many cars with ove 200k miles with no rear end noise.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Rear end noise

Reply #7 –
A light moan starting around 30 mph which goes away in coast condition sounds like gear whine to me.  And truly, Id be surprised if most of these cars dont have some whine if one listens carefully.

Rear end noise

Reply #8 –
Quote from: CatWoman;459505
So why do you think I'd have a worn axle?  And how do you tell, by looking?
Because the rear wheel bearings run directly on the axle shaft. There is no inner race, the rollers run directly on it. My 88 Cougar and 87 parts TC, which I used the rear end from in my 88 Sport, both had this issue. With the Cougar parts were still available so it wasnt the end of the world. With the TC rear end I used one of the axles from my 7.5" rear that I removed. You can tell if the axle is worn when you pull it out, you'll see the galling on it where the bearings chewed it up.
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Rear end noise

Reply #9 –
Yeah if it's a rumbling noise(not whine) it's possibly a bad axle/bearing... I had to replace the left side bearing and axle on my 1st Turbo Coupe at around 90K mi...

Rear end noise

Reply #10 –
I had the same issue on my 85 TC.  Felt like and sounded like it was coming from all over the car but ended up being a the beginning of the end for the driver side rear axle.

So is it a whine or rumble?  Are you getting any associated vibration with it?

For me I would check the brakes as mentioned, then check the driver shaft for bad u-joints, then I would check for excessive end play or runout of the pinion, and the easy check would be the control arm bushings.  The next thing would be the axles and axle bearings, then it would move into the third member with gears and associated bearings.  A long shot would be a bad or out of balance tire but that is a huge long shot.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp
 

Rear end noise

Reply #11 –
Thanks guys for all the help, took the Cat in for bearings yesterday and sadly the axles were worn scarred, had to use the big thick bearings because no one in my town had axles.  I'll run it till these bearings wear out then replace everything back new.  pinion gear good, brakes fine, differential gears good, haven't checked control arm bushings yet, but the car is super quiet driving on the road!  Money well spent even if the tire store did rip me off.